Sunday, December 27, 2009
Russell's dogs' table
I drew this image recently after reading a wonderful book called How Dogs Think by Stanley Coren. The outer eye represents the human color spectrum and the inner the dog, or that is what we think dogs see based on experiments.
It is a translation of my view of the world to hopefully some semblance of what my
Jack Russel, Kirby sees. Dogs see the world mostly in yellow and blue, with some degrees of black, brown, and grey. I understand now why he often used to lose the orange and yellow tennis balls in the grass if he couldn't smell them. Basically they both looked like the same color. Dogs eyes turn red into black, green into a brown-yellow, purple into blue.
Unlike my vision which has been selected to see multiple colors(probably based on the dietary fruit gathering) my dogs vision has been selected to see better at night and while moving. Both of these abilities would allow him to better catch prey at night. While that is not how he currently puts food in his dish, it is worth understanding for a couple of reasons.
The fact that a dog can not see in color means that he/she has no evolutionary relationship with fruits and vegetables(they do have the taste receptors for them but their % of a canine diet would have been low. They would also not have participated primarily in the selection/rejection process). Canis loopus have always been carnivores and many of the current dog and people foods are on a long time scale, quite recent additions. Like many in our population dogs may also have difficulty with cereal grains, sugar, and processed starches. Yet these can be some of the main ingredients in commercial dog foods. I try my best to steer clear of those. Kirby eats mostly raw beef, chicken, pork and bones or organ meat. I occasionally give him some yogurt(the no sugar or corn syrup variety). His treats are cuts of chicken or duck jerky that you can get at target/cub foods. I occasionally give him fruits and vegetables. He likes purple cabbage andI now know he can see it as the color blue. He has never needed to go to the vet yet and is in good health. My wife often complains that our apartment looks like a graveyard. Well...maybe.